Given parameters:
Percentage gain = 300%
Selling cost last year = $2420
Unknown:
Selling cost this year = ?
Solution:
To solve this problem;
Profit percent =
![(Selling cost this year - Selling cost last year)/(Selling cost last year) x 100](https://img.qammunity.org/2021/formulas/mathematics/college/6ut1m7rzlvdj3vsoja9una0o9angiqrjdu.png)
300 =
![(S - 2420)/(2420) x 100](https://img.qammunity.org/2021/formulas/mathematics/college/a372q1bysidbbkysj6awax5maamw47gmx8.png)
3 =
![(S - 2420)/(2420)](https://img.qammunity.org/2021/formulas/mathematics/college/wluyzefaqmk79cnk859xrxam8i5mhk2l36.png)
S- 2420 = 7260
S = $9680
To make a 300% gain, Jefferson Middle school needs a $9680 from fundraiser sales this year.